Bed motion



June 1, 193.7.. F. w. SEYBOLD BED MOTION '4 sheets-sheet 1 A Filed Sept.2l, 1935 June 1, 1937. F.. sEYBoLD BED MOTION Filed sept. 21, 19:55 4sheets-sheet 2` Junel, 1937. Fgw SEYBOLD 2,082,183

BED MOTION Filed Sept. 2l, 1955 4 Sheets-Sheet 3 Jung l, 1937. F. w.sEYBoLD BED MOTION Filed sept. 21, 1935 4 sheets-sneak;

Patented `une 1937 UNITED STATES BED MOTION Frederick W. Seybold,Westfield, N. J., assigner, by mesne assignments, to American TypeFounders Company, Elizabeth, N. Jaa corporaltion of New JerseyApplication September 21, 1935, Serial No. 41,607

25 Claims.

This invention relates to reciprocating bed motions or the like and moreparticularly to mechanism of this character especially adapted to beembodied in printing presses of the lat bed and r cylinder type.

It .is the principal object of this invention to provide a novel andimproved reciprocating bed motion by means of which a bed may beoscillated in a complete cycle, the greater portion of lo the movementof the bed in one direction being at substantially constant speed, whilein the other direction the bed has a continually varying velocity.

A further object of the invention is to provide 5 a bed motion for thispurpose in which all of the bed driving gearing remains constantly inmesh, and in which no cams, gates, latches, locks or any intermittentlyoperating reversing gear is employed. To attain this object, myinvention in 20 its preferred embodiment contemplates the provision of aplurality of differently proportioned trains of mechanism includingcranks, gears and sliding cross-heads which may be driven from a commonsource of power and which are adapted 5 to be continuously, positively,and operatively connected with said bed through means which is .adaptedto compound the movements imparted by said trains and to transmit theresultant of these movements to the bed.

30 Another object of the present invention is the provision of a bedmotion of this type, the stroke of which is longer than in the case ofthe stand-v ard 3: 1 bed motion, thus affording increased form rollercoverage for a given cylinder diameter.

35 Still another object is to provide bed driving mechanism composed ofparts which can be readily produced on standard machine tools at lowcost.

Other objects and features of novelty will be apparent from thefollowing specification when read drawings in which one embodiment of myinvention is illustrated by way of example. The drawings also includefigures representing graphically the development of the'theoriesunderlying my invention.

In the drawings:

Figures 1-4 inclusive depict graphs illustrating the development of thedesired velocity ratio curve of the reciprocating bed;

Figures 5 and 6 are diagrams showing the paths or orbits of certaincrank pins which impart the two separate motions which are components ofthe resultant motion finally imparted to the bed;

Figure '7 is a view in side elevation, with certain parts broken away,of an illustrative model of a printing press of the bed and cylindertype to which the principles of my invention have been applied;

in connection with the accompanying Figure 8 is a view of the press intransverse vertical section taken on line 8--8 of Figure 7;

Figure 9 is a longitudinal Vertical sectional View taken on line 9-9 ofFigure 8;

Figure 10 is a fragmentary longitudinal vertical sectional view taken online lil-I0 of Figure 8;

Figure 11 is a similar view taken on line l I-I l of Figure 8;

Figures l2 and 13 are exploded perspective views of the main portions ofthe two trains of mechanism which develop the resolved motions; and

Figure 14 is a View in perspective of the travelling gear and its crankarms by means of which the two component motions are compounded andimparted to the reciprocating bed.

In the printing art, it has long been recognized as desirable, duringthe printing period of a press of the kind illustrated, When thereciprocating type bed and the rotary impression cylinder are in rollingContact, that these members be moving at a uniform linear velocity so asto prevent marring the impression, and insure proper registry. Numerousexpedients have been proposed to attain this condition of uniform speed,but these have for the most part depended upon a plurality of differentdriving mechanisms for alternately driving the bed during differentportions of its printing and return strokes an-d also for reversing thebed at the ends of the strokes; or they have employed cam grooves or thelike to give a substantially constant velocity to the type bed duringprinting.

According to the present invention, however, the train of mechanismcomprising the driving transmission of the press is always in gear andexerting a positive force upon the bed, while at the same time elaboratecam and clutch mechanisms have been eliminated; it being possible toeconomically manufacture all parts comprising the bed motion on standardmachine tools.

Areciprocating bed, actuated by a sliding crosshead or yoke driven by asimple crank arm, as in the case of the familiar Scotch yoke, would havea linear velocity which varies at every point, attaining a maximum atmid-stroke and amounting to zero at the points of reversal at the endsof the strokes. This movement is one of pure simple harmonic motion, thegeneral velocity equation of .which Vb=wR. cos 0, where 0 is the anglethe crank makes with the horizontal. The velocity ratio curverepresenting the relation of the velocity of the bed and the constantlinear velocity of the crank pin is, of course, the familiar sinusoidillustrated in Figure 1 of the ydrawings, and is expressedin this caseby the equation y=100 cos 0.

As has been explained, the problem is to flatten one of the loops ofthis velocity ratio curve so as to produce a constant speed during theperiod when printing takes place. The mechanical attainment of thisdesiredresult` by means of my invention can be briey explained asfollows. The flattening of the loop of the simple harmonic velocityratio curve which represents the printing stroke can be accomplished bythe super-position of certain other simple harmonic motions upon thefirst motion represented by the curve in Figure 1. The velocityratioequation representing these combined motions is then integrated sothat the displacement equation of the bed movement may be obtained.ThisV displacement equation is then split into two separate equationswhich are recognizable as representing the displacement equations ofhypotrochoids. A hypotrochoid being the path of apoint on the radius orradius produced of a, circle rolling inside of a xed circle, theseorbits may b e obtained by means of a crank fastened to a pinion whichmeshes with and rolls within a xed internal gear, the pinion rotating onan arm which is preferably driven at a constant speed. In developing theresultant movement, each of the cranks is made to oscillatea slidingcross-head by means of a pin and slot connection, and the motions ofthese cross-heads, which are the projections of the hypotrochoidalmovements of the crank pinv on ahorizontal line, may be added orcompounded mechanically by means of a travelling gear, the axis' ofwhich is connected with the cross-heads by means of rigid crank armshaving pin and slot connections therewith. The travelling gear, ofcourse, is adapted to roll on a xed rack and to mesh with a rack carriedby the reciprocating bed, thus doubling the motion of the gear asapplied to the bed. The proportionate dimensions vof the cranks andgears comprising the transmission thus described, in order to attain theconstant velocity phase of the bed cycle, may be obtained from theequations. The development of these constructions" and their relativedimensions will now be setforth in detail.

In the graphs comprisingfFigures 174 inclusive, the crank angles are theabscissas and the velocity ratios in either direction are the ordinatesandare graduatedI in plus and minus quantities upwardly and downwardlyfrom the zero line, which, of course, indicates the point of change ofdirection of'movement. lIn Figure l, the simple harmonic curve I isrepresented by the equation y1=100 cos 0. In Figure 2 there is Shown asecond simple harmonic curve II represented by the equation 312:@cos,20. If these equations I and II be combined or added there isobtained the equation 111,2: cos @-l-a. cos 20 represented by the curveI, II in Figure 3. It will be noted that the velocity ratio curve ofthis combined harmonic motion shows a sharper loop at the beginning anda somewhat ilatter portion between the and 240 points of the cycle.

A third simple harmonic curve III is also shown in Figure 3 and may beexpressed by the equation ya=b cos 30. When this third curve issuperposed upon the curve I, II the resultant curve is as shown inFigure 4 in which the portion from 120 to 240 is for all practicalpurposes a straight line. The portion of the cycle containing this flatsectionor constant velocity ratio may be employed onv the printingstroke and the continuously Variable velocity ratio section representedby the first loop of the curve I, II, III may be employed von the returnstroke.

The resulting equation represented by the curve I, II, III in Figure 4is y1,2,3=100 cos H-l-a cos 20+b cos 30 in which the values a and b havebeen selected so that for values of 0 between 120 and 240 the velocityy1,2,a will remain constant and equal to approximately These values of aand b have been determined as being 46.5 and 10 respectively in order togive an approximately constant velocity between 120 and 240. The averagevalue of y1,2,3 is 63.47. Substituting these values for a and b, theequation for the desired velocity ratio curve shown in Figure 4 becomesy1,2,3=1o0 cos @+465 cos 20+'1'o eos 3a 1) Now in order to determine theratios of the physical dimensions of thel parts that will produce a bedmotion having the properties of the resultant velocity ratio equation,the next step is to integrate the velocity ratio equation for 111,2,3 toobtain the displacement equation giving the value of the lineardisplacement s1,2,3. Thus sm: fioo cos (a4-46.5 cos 20+1o cos `sa (2) Inorder to reduce the size of the cranks and gears embodied in the bedmotion so as to make the device practical for printing presses and thes1'23=100 sin 0+ 23.25 sin 20+? sin 30 like and still obtain arelatively long bed stroke, i

recourse is had to the well known multiplying or travelling gear.Therefore, the displacement of the latter is one-half that of thereciprocating bed, making the equation for the displacement of thetravelling gear S,=`-2-"=5o sin 0+11.625 sin 20+ sin 30 (4) s1=f sin@+2325 sin 20 (5) and On these assumptions, the following two equationsmust be true: v

The partial Equations (5) and (6) will be recognized as being of thegeneral lform:

s2=g sin @+150 sin 36 s=clc sin @+o sin (1n-1)@ (9) this equationexpressing the ordinate of a hypotrochoid which, as has been alreadystated, is

the path generated by a crank pin fastened to a pinion which meshes withand rolls in a fixed internal gear, the pinion rotating on an arm whichfor these purposes is driven at a constant speed.

In Equation (9), v Y

in the `9the displacement of the cross-head of one of the transmissions,

c=the length of the crank on the pinion,

clc=the length of the crank arm on which the pinion rotates, i. e., thedistance between centers of the pinion and internal gear,

m=the gear ratio between the internal gear and the pinion,

0=the angle of rotation of the pinion driving crank arm.

In order that each cross-head shall have travelled approximately thesame distance when 0=66 1 or 293 59 the constants f and y are determinedfrom Equations (5) and (6) as follows:-

Substituting the values for f and g in Equations (5) and (6)respectively,

s1=40 sin i-23.25 sin 26 (14) and 52:60 sin 0|10/3 sin 30 (15) Adding(14) and (15) gives s1,2,3= sin @+2325 sin 20|10/3 sin 30 (3) Equation(9) indicates that the gear ratio m for Equation (5) must be 3, and forEquation (6) the value of m equalsV 4, in order to give sin 20 and 30respectively.

From Equations (4) and (8), we find that s, (the displacement of thetravelling gear)=s1-s2 Therefore, the length of the crank which drivesone of the cross-heads is -.SSIZS times the center distance between thepinion and the internal gear within which it rolls. In the othertransmission the length of the crank which drives the cross-head is'--wOSSS times the center distance between this pinion and itsassociated internal gear.

The actual sizes of the internal gears and the pinions, and of the otherelements comprising the transmission depend of course on the size of thesheet to be printed and form roller coverage that is desired, whichdetermines the length of the press bed stroke.

With the hypotrochoid equations developed above and the values whichhave been obtained to t the requirements for producing the bed motionvelocity ratio curve illustrated in Figure 4, the actual orbits of thecrank pins which describe the hypotrochoidal paths may be reproducedgraphically as in Figures 5 and 6. The rst transmission with its crankratio of .58, as

developed inthe preceding paragraphs, and its gear ratio ofv 3:1, willyield a motion whose orbit is represented by the curtate hypotrochoid A1in Figure 5.. The circle B1 represents the internal gear and the circleC1 represents the pinion whose crank arm is designated c1. Thehorizontal displacement of the crank pin D1 in this diagram isrepresented by s1, the angle made by the crank 'c1 with the centerdistance between the pinion and the internal gear being shown as 30.

The diagram of the motion developed bythe second transmission train isrepresented in Figure 6 in which the path of movement of the crank pinD2 is a prolate hypotrochoid shown at Az, the internal gear is indicatedat Bz, the pinion at C2 and the crank arm at cz, the length of this lastelement being relatively small, the horizontal displacement of the crankpin being indicated at s2.

The actual mechanical details of the particular motions which have beenreferred to in connection with the developments just described, will nowbe referred to in connection with the appropriate constructional guresof the drawings.

For the sake of clearness, there has been illustrated in the drawings amodel of a press embodying the principles of the invention in whichnumerous details which are not essential to the illustration of thedevelopment of the bedv motion are omitted. The press is of the flatbed, two revolution, constant speed cylinder ltype and is provided witha base I0 upon which are mounted the side frames I2 which are providedwith suitable bearings for the axle I3 of the'impression cylinder I4.'I'he reciprocating type bed is illustrated at I5 and is provided in theillustrative model with suitable guides I6 in the side frames I2. Itwill be realized, of course, that in a practical embodiment of theinvention in an actual press the bed may be provided with the usualroller tracks and other refinements and accessories. A common driveshaft 20 having suitable bearings in the side frames is employed todrive both the bed and the impression cylinder and is itself adapted tobe driven by a suitable motor. Upon the drive shaft are secured thepinions 2|, 22 and 23. 'Ihe pinion 2I mounted on an end of the driveshaft 2D exteriorly of one of the side frames I2 meshes with the gear 2twhich is mounted upon the stud 25 and in turn meshes with the impressioncylinder gear 26. The ratios of this train of gearing are selected so asto give a constant angular Velocity to the impression cylindercorresponding to the linear velocity of the bed during the printingstroke. able means are provided for raising rthe impression cylinder outof contact with the bed during non-printing periods.

The pinions 22 and 23 carried by the drive shaft 20 serve to effect themovements of the two transmission trains, which may for convenience begiven the general designations L and M, and which develop the componentmotions which are combined and applied to the bed. The pinions 22 and 23mesh with the large gears 28 and 3B which turn on the stub shafts 3l and32 respectively, each making one revolution per cycle. Intermediate theside frames I2 there are provided longitudinally extending bedsupporting frames 34 and 35 which are cut out to receive the stationaryinternal gears 36 and 3l respectively. The pitch circles of theseinternal gears 36 and 3l correspond with the circles B1 and B2 on thediagrams in Figures 5 and 6. The large gear 28 of the train Lis providedwith a shaft 39 Of course, suitupon which a pinion 40 is rotatablymounted. The pinion 40 is adapted to mesh with the internal gear 36 androll within the same, this pinion being indicated diagrammatically inFigure 5fat C1. As deduced mathematically, the gear ratio of theinternal gear 36 and the pinion 40 is 3:1. In the transmission train M asimilar shaft 4| is carried by the gear 3|! and provides an axle for thepinion 42 which rolls in mesh with the internal gear 31, the ratiobetween the two being 4:1. The pinion 42 is represented in Figure 6 bythe circle C2. A crank disc 44 is rigidly secured to the pinion 40 andis provided with a crank pin 45 and the pinion 42 carries the crank disc41 which is provided With the crank pin 48. The cranks 44 and 41 arerepresented in the diagrams in Figures 5 and 6 by the lines ci and c2and the crank pins 45 and 48 are indicated at the points D1 and D2. Bymeans of the trains of gearing which have just been described, the crankpins 45 and 48 are made to describe the hypotrochoidal orbits indicatedat A1 and A2 in Figures 5 and 6.

Longitudinally slidable within grooves formed in the base U and the typebed |5 are the slotted cross-heads 50 and 5|. These cross-heads orslides are shown very clearly in elevation in Figures 10 and 11respectively of the drawings. The cross-head 50 is provided with ahorizontally extending slot 53 which permits the passage of the driveshaft 2U without hindrance during the sliding movements of thecross-head. A vertical slot 55 is alsocut in the cross-head 50 withinwhich the squared block 55 is adapted to reciprocate, this block beingrotatably carried by the crank pin 45 duringpits complex movement. Itwill thus be seen that the cross-head 50 is reciprocated longitudinally`through a cycle of movement which is the projection of thehypotrochoidal movement of the crank pin 45 upon a horizontal lineparallel with the bed l5. Similarly the cross-head 5| is provided with aclearance slot 51 for the drive shaft 20 and a vertical slot 58 forreceiving the block 60 carried by the crank pin 48 of the transmissionM, and the motion of the slide 5| is the projection of thehypotrochoidal movement of the crank pin 43 upon the horizontal.

In order to compound these projected hypotrochoidal movements developedby the transmission trains L and Mrand impressed on the slides 58 and5|, the following mechanism is provided, which is designated generallyby the reference character N. (See particularly Figure 14.) Upon acentrally located support 62 there is provided a stationary rack 63.Upon the underside of the bed I5 there is provided a bed driving rackG4. Arranged so as to roll upon the stationary rack 83 is the travellinggear 55 which also meshes with the bed rack 84, thus multiplying itslongitudinal movement as applied to the bed. The travelling gear 65 isprovided with an axle 66 upon which it is rotatably mounted and whichcarries at its respective ends the blocks 61 and 88 which arerespectively adapted to slide in the horizontal slots B9 and 180i theslides 50 and 5|. Rigidly secured to the axle 55 are the oppositelyextending crank arms 14 and 15 having crank pins 16 and 11 respectivelyupon which are rotatably carried blocks 18 and 19. The block 18 isguided within the vertical slot 86 formed in the cross-head 50 and theblock 19 within the slot 8| formed in the cross-head 5|. It will thus beseen that the complex reciprocating movements of each of the cross-heads58 and 5| are transmitted through their respective crank arms 14 and y15.to `the axle of the'travelling gear 65 and are thus compounded andapplied through the gear (i5-andthe racks63 and 64 to the bed.

It will be readily'seen from the foregoing descriptions that there isvprovided by this invention a reciprocating bed movement which may bedriven from a constantly rotating source such as the drive shaft 20 andtransmission mechanisrn interposed between this source of power and thebed which comprises the trains L and M each of which develops a motionwhich corresponds to the lpartial Equations (5) and (6) set forth in theearlier portion of the present specication, and which also compriseslthe motion compounding mechanism N which receives the two componentmotions and combines them to obtain a motion, the displacement equationof whichis Equation (3) as set forth above. This motion is imparted tothe bed by the `travelling gear and the constant velocity requirementsof the printing stroke thereof are satisfied in accordance with thegraph in Figure 4 of the drawings.

It might be observed also that in this construction the length of thebed stroke is 3.390 times the diameter of the impression cylinder ascompared to the ratio of 2.761 obtained with a conventional 3:1 bedmovement. The present embodiment, as already pointed out, is alsodistinguished by the feature of continuous gearing engagement andemploys no auxiliary driving mechanisms, locks, gates, cams or latches;

The invention may be embodied in bed motions which differ somewhatinsofar as the design and arrangement of their functioning parts areconcerned, but each such embodiment includes at least two operatingparts or portions thereof which are caused to move along cyclic paths,which paths are dissimilar in character, while maintaining constantphase relationship therebetween, and which comprise portions of the beddriving means. These parts are designated driving elements in ,claimsappended hereto, and where it is stated that the elements move withoutretracementit lis meant that they move continuously in one directionalong their respective closed orbits andnever` retrace their pathsduring any single cycle of movement.

It will be further understood that various changes and modifications maybe made in the embodiment illustrated more or less diagrammatically inthe drawings, and described herein, without departing from the scope ofthe invention as dened by the following claims.

Having thus described the invention, what is claimed as new and desiredto be secured :by Letters Patent is: Y v

1. A bed movement of the type in which the bed during its working andreturn stroke is reciprocated in a plane, comprising the combinationwith the bed and means for supporting the same for planar movement, of aplurality of movable driving elements, means forY moving said elementsrespectively, without retracement along dissimilar cyclic paths whilemaintaining constant phase relationship therebetween, and meansmaintaining a constant operative connection between said elements andthe bed, said means receiving motion from both of said elementslandtransmitting to the bed a motion which is the resultant of the motionsof said elements, whereby the bed is caused to move at substantiallyconstant `speed during the major portion of its movement in onedirection.

2, A bed movement of ,thevtype in which theV bed during lits, workingand return` stroke is reciprooated in its own plane, comprising thecombination with the bed and means for supporting the same for planarmovement, of two movable driving elements, means for moving saidelements respectively, without retracement along dissimilar cyclic pathswhile maintaining constant phase relationship therebetween, said pathslying in parallel planes which are normal to the plane of Said bed, andmeans maintaining a constant operative connectionbetween said elementsand the bed, said means receiving motion from both oi said elements andtransmitting to the bed a motion which is the resultant of the motionsof said elements, whereby the bed is caused to move at substantiallyAconstant speed during the major portion of its movement in onedirection.

3. A bed movement of the type in which the bedV during its working andreturn stroke is reciprooated in a plane, comprising the combinationwith the bed and means for supporting the same for planar movement, of aplurality of movable driving elements, means for moving said elementsrespectively, without retracement along dissimilar cyclic paths whilemaintaining constant phase relationship therebetween, and meansmaintaining a constant operative connection between said elements andthev bed, said means receiving-motion from both of saidv elements andtransmitting-to the bed a motion which is the resultant of the motionsof said elements, whereby the bed is caused to move at substantiallyconstant speed during the major portion of its movement in onedirection, said last named means comprising aplurality of slidingcrossheads, each of which is respeotivelyjdriven by one of said drivingelements, and means for operatively connecting said crossheads to saidbed.

4. A bed movement of the type in which the bed during its Yworking andreturn stroke is reciprocated'irnma plane, comprising the combinationwith the lbed and means for supporting the same for planar movement, ofa plurality of movable driving elem-ents, means for moving said elementsrespectively, without retracement along dissimilar cyclic paths whilemaintaining constant phase relationship therebetween, and meansmaintaining a constant operative connection between said elements andthe bed, said means receiving motion from both of said elements andtransmitting to the b-ed a motion which is the resultant of the motionsof said elements, whereby the bed is caused to move at substantiallyconstant speed during the major portion of its movement in onedirection, saidjlast named means comprising a plurality of slidingcrossheads, Aeach of which is respectively driven byI oneof said drivingelements, and a travelling geardriven by both of said slidingcrosshea'ds and meshing with a rack on said bed.

5. A bed movement of the type in which the bed during itsv working' andreturn stroke is reciprocated in a planeQc'cmprising the combinationwith the bed and means for supporting the same for planar movement, of aplurality oi movable driving elements', rne'ans'ror moving said elementsrespectively, without retracement along dissimilar cyclic paths whilemaintaining constant phase relationship therebetween, and meansmaintaining a constant operative connection between said elements andthe bed, said means receiving motion from both oi said elements andtransmitting to the bed amotion which is the resultant of the motions ofsaid elements, whereby the bed is caused to move'at substantiallyconstant speed during the major portion of its movement in onedirection, said` last named means comprising a, common member guidedfor-reciprocationin the' same direction as that ofv said bed, drivingconnections between said elements and said member, and means foroperatively connecting said member to i said bed.

6. A bed movementfof the .type in which the bed duringv itsworking andreturn stroke is reciprocated ina plane, comprising the combination withthe bed and means'. for supporting the same for planar movement, of. aplurality of movable driving elements, means forA moving-said elementsrespctivelmwithout retracement along dissimilar cyclicI paths` whileYmaintaining. constant phase relationship therebetween, and meansmaintaining a constant operative connection between said elements andthe bed, `saidmeans receiving motion from both of saidelements andtransmitting to thebed a motion which is the resultant oi the motionsvof said elements,whereby the bed is caused to move at substantiallyconstant speed during the major portion of its movement in onedirection,- said last named' means comprising a common member tiltableabout a center of rotation which is guided for` reciprocation in thesame direction as that of 'said bed,connections between said elements`and points on said'mernber spaced from said center of rotation,andmeans for operatively connecting said member to said bed.

7. A bed'movement of the type in which the bed duringits working andreturn stroke is reciprocated in a plane, comprising the combinationwith the bed and means for supporting the same for planar movement, 'ofa plurality of movable driving elements, means for moving said elementsrespectively', without retracementalong dissimilar cyclicvl paths whilemaintaining constant phase relationship therebetween, and meansymaintaining a constant operative connection between said elements andthe bed, said means receiving mo-v tion from both of 'said elements andtransmitting to the bed a motion which is the resultant of the motionsof said elements, whereby the bed is caused to move at substantiallyconstant speed during the major' portion of its movement in onedirection,vv said ,last named means comprising a common member whichcomprises a lever arm having an axle thereon, connections between saidelements and 'spaced points on said lever arm, a travelling gearrotatably mounted on said axle and meshing with a rack on said bed.

8.`A bed movement of the-type in which the bed during its working andreturn stroke is reciprocated in a plane, comprising the combinationwith the bed and means for supporting the same for planar movement, of aplurality of movable driving elements, means for moving said elementsrespectively, without retracement along dissimilarl cyclic paths whilemaintaining constant 'phase relationship therebetween, and meansmaintaining a constant operative connection between said elements andthe bed, lsaid means receiving motion from both of said elementsandtransmitting to the bed a motion which is the resultant of the motionof said elements, whereby the bed is caused to move at substantiallyconstant speed during the major portion of its movement in onedirection, said last named means comprising a stationary rack, a rack onsaid bed, a travelling gear adapted to roll on said stationary rack andmesh with said bed rack, and means for operatively connectingV each ofsaid driving elements with said gear.

9. A bed movement of the type in which the y bed during its working andreturn stroke is reciprocated in a plane, comprising the `combinationwith the bed and means for supporting the same for planar movement, of apluralityxof movable driving elements, means for moving said elementsrespectively, without retracement along.

dissimilar cyclic paths While maintaining constant phase relationshiptherebetween, each of said paths being hypotrochoids, and means main--taining a constant operative connection between said elements and thebed, said means receiving,

motionfrom both of said elements and transmitting to the bed a motionwhich is the resultant of the motions of said elements, whereby the bedis caused to move at substantially constant speed during the majorportion of its movement in one direction.

10. A bed movement of the type in which the I bed during its working andreturn stroke is reciprocated in a plane, comprising the combinationwith the bed and means for supporting the same for planar movement, of aplurality of movable driving elements, means for movingsaid elementsrespectively, without retracementl along dissimilar cyclic paths whilemaintaining constant phase relationship therebetween, one of' said pathsbeing a prolate hypotrochoid andthe other a curtate hyprotrochoid, andmeans maintaining a constant operative connection between said elementsand the bed, said means receiving motion from both of said elements andtransmitting to the bed a motion which is the resultant velocity of thebed to the velocity of the cori-l stantly rotatably driving element, and=the angle of movement of said element.

12. A bed movement as set forth in claim 1,r

in which the resultant movement of the bed is compounded of three simpleharmonic motions, said motions being described respectively bythefollowing sinusoidal equations: y1=100 cose; y2: 46.5 cos and :113:10cos 30. l

`13. A reciprocating bed movement comprising -4 a rectilinearlyreciprocating bed, a rack ori-said, bed, a stationary rack, a travellinggear adapted i to roll on said last named rack and mesh with said bedrack, a plurality of sliding-cross-heads operatively connected with saidgear, and a. separate train of gearing operatively connected withl eachof said cross-heads and adapted to impart motions to said cross-headswhich are compounded and the resultant motion imparted to said bedthrough said gear.

14. A reciprocating bed movement comprising a rectilinearlyreciprocating bed, a rack on said` bed, a stationary rack, a travellinggear adapted,

to roll on said last named rack and mesh with said bed rack, a pair ofsliding cross-heads, a

,lever carrying an axle for said travelling gear,

and projecting studs at spaced points thereon, each of said studs beingslidably received in a slot in one of said cross-heads and means fordriving each of said cross-heads.

`15. A reciprocating bed movement comprising."v a rectilinearlyreciprocating bed, a rack on said bed, a stationary rack, a travellinggear adapted to roll on said last named rack and mesh with said bedrack, a pair of sliding cross-heads, a

lever carrying an axle for said travelling gear;

and projecting studs at spaced points thereon,v

each of said studs being slidably received in a slot in one of saidcross-heads, and separate means for imparting different movements toeach of said cross-heads.

16.A reciprocating bed movement comprising a rectilinearly reciprocatingbed, a rack on said bed,=a stationary rack, a travelling gear adapted toroll on said last named rack and mesh with said bed rack, a pair ofsliding cross-heads, a lever carrying an axle for said travelling gear,and projecting studs at spaced points thereon, each of said studs beingslidably received in a slot in one of said cross-heads, crank pinsrespec- Y tively slidable in other slots in said cross-heads, andseparate trains of gearing for moving said crank pins.

17. A reciprocating bed vmovement comprising a rectilinearlyreciprocating bed, a pair of trains of mechanism each comprising a crankarm or its equivalent and each rotated at the same angular velocity, acrank pin thereon, a pinion on said crank pin, a fixed internal gearwith which said pinion meshes and Within which it rolls, another crankrigid With said pinion and having a crank pin thereon, said trainshaving different gear and crank arm ratios, means for oper'- ativelyconnecting the last named crank pins of each train with said bed forimparting theretol a motion which is a resultant of the combined motionsof said last named crank pins.

18. A reciprocating bed movement comprising a rectilinearlyreciprocating bed, a pair of trains of mechanism each comprising a crankarm or its equivalent and each rotated at the same angular velocity, acrank pin thereon, a pinion on said crank pin, a fixed internal gearwith which said pinion meshes and Within'which it rolls, an-

other crank rigid with said pinion and having acrank pin thereon, saidtrains having different gear and crank arm ratios, means for operativelyconnecting the last named crank pins of each train with said bed forimparting thereto a motion which is a resultant of the combined motionsof said last named crank pins, the gear ratios of the internal gears andthe pinions in the case of onev train being 3:1 and the other 4:1, andthe respective ratios of the last named cranks to the first named crankarms being approximately .58 and .055.

19. A reciprocating bed movement comprising a rectilinearlyreciprocating bed, a plurality of trains of mechanism each comprising acrank arm or its equivalent rotated at a constant angular velocity, acrank pin thereon, a. pinion on said crank pin, an internal gear withwhich said pinion meshes and within which it rolls, another crank rigidwith'said pinion and having a crank pin thereon, a plurality of slidingcross-heads driven by said last named cranks, each having a slot thereinwithin which one of said last named crank pins is adapted to slideduringitsmovement, a rack on said bed, a fixed rack, and a travellinggear adapted to roll upon said xed rack and mesh with said bed rack, anaxle upon which said travelling gear turns, a plurality of armsextending from said axle and each adapted to be driven by one of saidsliding cross-heads through crank pins on said arms which are adapted towork in other slots in said cross-heads.

20. In a reciprocating bed movement, the combination with arectilinearly reciprocating bed of a main driving member for actuatingsaid bed movement and adapted tol rotate at a constant angular velocity,transmission mechanism opera.-

tively interposed between said member and said bed and adapted to impartto said bed a rectilinear cyclic motion, a substantial portion of whichis uniform, said transmission mechanism comprising a plurality ofdriving elements, means driven by said main driving member torespectively move each of said elements in a separate hypotrochoidalorbit which is symmetrical about its diameter which lies in a planewhich is transverse to said bed, a plurality of members adapted toreciprocate in directions parallel to that of the movement of said bed,driving connections between saiol reciprocating members and said drivingelements respectively for giving said reciprocating members rectilinearcyclic motions which are represented by the projections of saidhypotrochoidal orbits upon their diameters which are parallel to theplane of movement of said bed; and means for combining the motions ofsaid last named members and transmitting the resultant to said bed.

2l.. In a reciprocating bed movement, the combination with arectilinearly reciprocating bed, of a main driving member for actuatingsaid bed movement and adapted to rotate at a constant angular velocity,transmission mechanism operatively interposed between said member andsaid bed and adapted to impart to said bed a rectilinear cyclic motion,at least one-third of the complete cycle of which is uniform, saidtransmission mechanism comprising two driving elements, means driven bysaid main driving member to respectively move each of said elements in aseparate'hypotrochoidal orbit which is symmetrica] about its diameterwhich lies in a plane which is transverse to said bed, two membersadapted to reciprocate in directions parallel to that of the movement ofsaid bed, driving connections between said reciprocating members andsaid driving elements respectively for giving said reciprocating membersrectilinear cyclic motions which are represented by the projections ofsaid hypotrochoidal orbits upon their diameters which are parallel tothe plane of movement of said bed; and means for combining the motionsof said last named members and transmitting the resultant to said bed,one of said orbits being a prolate hypotrochoid and the other a curtatehypotrochoid.

22. In a reciprocating bed movement, the combination with arectilinearly reciprocating bed, oi a main driving member for actuatingsaid bed movement and adapted to rotate at a constant angular velocity,transmission, mechanism operatively interposed between said member andsaid bed and adapted to impart tol said bed a rectilinear cyclic motion,at least one-third of the complete cycle of which is uniform, saidtransmission mechanism comprising a gear train, a driven element ofwhich has an orbit which is a hypotrochoid which is symmetrical aboutits diameter which lies in a plane transverse to said bed, a second geartrain having a driven element the orbit of which is a. hypotrochoid ofdiiTerent characteristics but also symmetrical about its diameter whichlies in a plane transverse to said bed; a member reciprocated by saidfirst named element in a straight line path parallel with the directionof movement of said bed in a cycle ofY movement which is the projectionof the movement of said rst named element along its hypotrochoidal orbitupon said straight line, a second member reciprocated in a straight linepath parallel to said first named path and having a cycle of movementwhich is the projection of the movement of said second named elementupon the second straight line path, and means for combining the motionsof said members and imparting the resultant to said bed.

23. A reciprocating bed movement comprising a rectilinearlyreciprocating bed; a plurality of trains of mechanism each comprising acrank arm or its equivalent driven at a uniform angular velocity, a.pinion rotatably carried on said crank arm, an internal gear, saidpinion meshing with and adapted to roll within said internal gear, acrank pin rigidly carried by said pinion; means for driving said rstnamed crank; means for operatively connecting the crank pins of eachtrain of mechanism with said bed and for imparting to the latter amotion which is the resultant o1" the combined motions of said trains.

24. A reciprocating bed movement comprising a a rectilinearlyreciprocating bed; two trains of mechanism each comprising a crank armor its equivalent driven at a uniform angular velocity, a pinionrotatably carried on said crank arm, an internal gear concentricallydisposed with relation to the center of rotation of said crank arm, saidpinion meshing with and adapted to roll within said internal gear, acrank pin rigidly carried by said pinion; the crank pin of one of saidtrains being disposed at a point upon the radius of its pinion, and thecrank pin of the other train disposed at a point on the extended radiusof its pinion; means for driving said first named crank; means foroperatively connecting the crank pins of each train of mechanism withsaid bed and for imparting to the latter a motion which is the resultantof the combined motions of said trains.

25. A reciprocating bed movement comprising a rectilinearlyreciprocating bed; two trains of mechanism each comprising a crank armor its equivalent driven at a uniform angular velocity, a pinionrotatably carried on said crank arm, an internal gear conc-entricallydisposed with relation to the center of rotation of said crank arm, saidpinion meshing with and adapted to roll within said internal gear, acrank pin rigidly carried by said pinion; the crank pin of one of saidtrains being disposed at a point upon the radius of its pinion, and thecrank pin of the other train disposed at a point on the radiusextended.l of its pinion; means for driving said first named crank;means for operatively connecting the crank pins of each train ofmechanism with said bed and for imparting to the latter a motion whichis the resultant of the combined motions of said trains; said last namedmeans comprising a rack carried by said bed, a stationary rack spacedfrom and parallel to said bed rack, a travelling gear adapted to rollupon said stationary rack and mesh with said bed rack; a pair of slidingcrossheads operatively connected With said travelling gear, and meansfor respectively driving said crossl'i-eads from said crank pins.

FREDERICK W. SE'YBOLD.

